Cooling electric apparatus



(No Model.)

W. S. MOODY.

COOLING ELECTRIC APPARATUS.

Patented Mar. 20,

UNITED STATES PATENT OFFICE.

WALTER S. MOODY, OF LYNN, ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF BOSTON, MASSACHUSETTS.

COOLING ELECTRIC APPARATUS.

SPECIFICATION forming part of Letters Patent No. 516,829, dated March 20, 1894.

Application filed July 1, 1883. Serial No. 479,349. (No model.) i

To all whom it may concern.-

Be it known that I, WALTER S. MOODY, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented a certain new and useful Improvement in Cooling Electric Apparatus, of which the following is a specification.

My invention relates to means for cooling electric apparatus, such as electric transformers, whereby excessive or dangerous heating of the coils in such appliances is prevented, and whereby the efficiency is increased by preventing increase of resistance to the current in the conductors forming its coils: and is especially adapted for use with large transformers or electrical apparatus, wherein the electric conductors are massed to form a bundle of considerable size, and are required to be surrounded by insulation capable of withstanding currents of moderate or high potentials; such insulation for current is nearly always a good insulator for heat also, preventing its ready escape from the coils. The coils or conductors are also surrounded by H01], in the laminae forming the core of a transformer, which acts to. prevent the free escape of the heat from thec'oils.

To carry out my invention, I establish a flow of cooling fluid or liquid through or about the transformer or other electric apparatus at a rate dependent upon and controlled by the flow of current through its coils; and to this end I'employ a pump, a blower, or other fluid propelling apparatus, operated bya motor device whose speed or power is dependent directly or indirectlyupon the current traversing the coils; in some instances, I employ conduetin g pipes or conduits leading to a casing surrounding the apparatus, or its coils, for conveying the fluid. Such pipes or conduits may also include a chamber for the cooling of the heated liquid or fluid coming from the transformer. Heretofore it has been proposed to cool such apparatus by a circulation of fluid brought about by the heat generated in the transformer itself, "or by what might be termed anatural circulation or draft; such an arrangement is not economical or efiicient, because it depends for its action upon the existence of .the evil itself. In other words, a natural circulation or draft will not take place I until the air or other cooling medium has bepated, and the circulation of the cooling medium depends, not upon the existence of heat in the electric apparatus, but upon the flow of current which would, in time, generate undue heat therein; and, in the improved arrangement herein described, immediately such current begins to flow, the rateof circulation of the cooling medium is automatically accelerated and excessive heating prevented; and the rapidity of the circulation keeps pace with the increasing current, or, in

some cases, may exceed that demanded. Furthermore, when the flow of current through the coils of the electric apparatus has nearly ceased, or has diminished to such an extent that special means for cooling it need no longer be used, there is no need of maintaining the circulation of the cooling medium; and, by my invention the circulation is at such times stopped automatically.

In the accompanying drawings, hereby annexed to and forming part of this specification, Figure 1, is a representatiompartly diagrammatic, of a transformer cooled according to my invention and Fig. 2, is a. modified form of motor-regulator which I may employ.

Therein, T is a transformer which may be of considerable capacity, and the larger its capacity the more need there will be for providing cooling arrangements when it is un der load. The transformer is shown as sur rounded bya casing, O, of iron. This casing may be made of any suitable material, dependent upon the position where the transformer is installed, and the character of the cooling medium passing through it: if the transformeris situated in a sheltered position, and air is used for cooling, the casing might be made of wood. The pipes P, P, P form a closed pipe system connecting the trans- 2 amaze former-casing 0, the cooling chamber or condenser R, and the.pump F. The pump F is shown as'operated by an electric motor M, whose armature coils form an induced .or see- 5 ondary winding on closed circuit, and whose inducing or field coils are shown at S, S, in the main line or circuit leading from an alternating current generator G to the transformer T. When no current flows in the coils S, S,

to that is, when the transformer 'l is doing no work, the motor M will not revolve; itis also evident that its rate. of revolution is dependent wholly upon the amount of current flow ing in the coils S, S, that is, the current going 1 5 from the generator G to the transformer, and therefore that the circulation of the fluid through the pipes P, P, P, depends upon the flow of current in the primary coils of the transformer; theheating eflfect increases with so the current flowing through the transformer coils. The motor M is arranged to increase its speed with increase of current, so that the desired circulatation is effected through the transformer. The cooling medium, which may be water, oil, or anyother suitable fluid, is shown as going to the reservoir B after passing through the transformer, thence to the pump, and again to the transformer, being used over and over again. If the coils of the transformer were so well insulated that water could be used instead'of an insulating ;fluid, like oil, and the supply of water was abundant, of course no arrangements for cooling it for repeated use after-it had passed 7 through the transformer would be required. Or, instead of usinga cooling liquid a blower, B, may be driven by the electric motor M andacooling stream of air forced to the transformer through the pipe P shown partly in o dotted lines, and out at P, also shown in dotted lines.

Fig. 2 shows an indirect method of accomplishing the same result, ora method in which the flow of current to or from the transformer 5 acts to stop, start, and regulate an auxiliary electric motor. Thus, the motor M is a direct current motor, the lines a, b, leading thereto receiving current from any suitable source. A leading wire to the transformer coils, primary or secondary, includes the coil S which,

when energized, pulls upon a core K in opposition to a retrac'tor or spring Z. The movement of the core K actuates a lever L and moves a switch governing the'flow of current in the motor M; it may also vary the amount of a resistance H in the circuit of the motor, to vary its speed or power, and the motor M may drive the pump F already mentioned, the blower B, or any similar apparatus. The motor M might of course be any kind of a motor, electric or not. It may be mentioned,

also, that while a pipe system has been shown former T, which would preferably be provided with openings or passages through which the air could circulate to convey away the heat.

Having thus described my invention, what I claim as new, and wish to protect by Letters Patent of the United States, is-

1. The method of cooling electric apparatus which consists in supplying to such apparatus a flow of cooling fluid proportioned to the current passing therein.

2. The method of cooling transformers or other electric apparatus herein set out and described, which consists in forcing through such apparatus a flow of cooling fluid automatically proportioned to the current passing therein.

3. As a means of cooling electric apparatus, a pump, a motor actuating such pump and governed by the current in the apparatus to be protected, and a system of pi pes'includiug a source of fluid supply and connecting the pump with the apparatus to be cooled.

4. In combination, a transformer, a pipe leading therefrom, a pump supplying a cooling fluid to such pipe, an electric motor driven by the current passing in the transformer and arranged .to operate the pump, and-a source of fluid supply; all arranged and adapted to supply the cooling fluid ata rate proportioned to the flow of current in the transformer.

5. In combination, a transformer, a blower forcing air through such transformer, and means, substantially as described and set forth herein, adapted to actuate the blower at a rate dependent upon the current passing in the transformer.

6. In combination, a transformer, ablower forcing air through pipes leading to such transformer, and an electric motor driven at a rate' dependent upon the current passing in the transformer, and adapted to operate the blower, substantially as described.

In witness whereof I have hereuntoset my hand this 29th-day of June, 1893.

' WALTER S. MOODY. Witnesses:

JOHN W. GIBBONEY, BENJAMIN B. HULL. 

